Cutter head assembly for routing and other machine tools



Nov. 29, 1932. GORTQN 1,889,653

CUTTER HEAD ASSEMBLY FOR ROUTING AND OTHER MACHINE TOOLS Filed Aug. 21, 1929 4 Sheets-Sheet 1 Nov. 29, 1932. GORTON w 1,889,653

CUTTER HEAD ASSEMBLY FOR ROUTING AND OTHER MACHINE TOOLS Filed Aug. 21. 1929 4 Sheets-Sheet 2 grwantoz will Nov. 29, 1932. GQRTQN 1,889,653

CUTTER HEAD ASSEMBLY FOR ROUTING AND OTHER MACHINE TOOLS Filed Aug. 21. l929 4 Sheets-Sheet- 3 Nov. 29, 1932. G RT N 1,889,653

CUTTER HEAD ASSEMBLY FOR ROUTING AND OTHER MACHINE TOOLS Filed Aug. 21. 1929 4 Sheets-Sheet 4 Patented Nov. 29, 1932 UNITED sures:

enonen eonron, or nnonvn, Wisconsin 7 CUTTER HEAD ASSEMBLY FOR EOUTIN G AND OTHER MACHINE TOOLS Application filed August 21, 1929. Serial No. 387,330.

This invention provides an improved cutter head assembly for routing and other rotary cutter spindle machine tools; and the objects and nature of the invention will be understood by those skilled in the art in the light of the following explanations of the accompanying drawings that show what I now believe to be the preferred mechanical expression or embodiment of my invention from among other constructions, arrangements and combinations within the spirit and scope of my invention.

An object of the invention is to provide an improved cutter head assembly for rotary 15 cutter spindles with the ends in view of increasing the accuracy of adjustments, the durability of operating parts and their accuracy in operation.

With the foregoing and other objects in G view, the invention consists in certain novel features in construction, assembly, arrangement or combinations, as more fully and particularly explained and specified hereinafter.

Referring to the accompanying drawings,

forming a part hereof:

Fig. 1 is a front elevation of the cutter head.

F Fig. 2 is a vertical section, on the line 22,

Fig. 3 is a detail elevation of the rotary cutter spindle before application of the ring for retaining the radial pins that-hold the collet against relative rotary movement, said cation of said ring.

Flg. 4 is an enlarged cross section on the 4 line 4.--4, Fig. 3.

taining the radial pins.

Fig. 7 15 an enlarged that is exteriorly applied to the cutter spindle to retain the radial pins.

pins being shown in operative position preparatory to securing bysubsequent appl1-' Fig. 5 is an enlarged cross section on the' F1g.- 3, the exterior ring for re-' tion of the lower end portionof the rotary cutter spindle taken on the line 6.6, Fig. 5 showing the permanent exterior ring forre-i section of the ring Fig. 8 shows the ring nut screwed intothe lower end of the barrel, in detail enlarged longitudinal section.

Fig. 9 shows the collet in enlarged eleva- I -tion.

Fig. 10 shows the collet enlarged in inner end elevation, but on a reduced scale with respect to the scale of Fig. 3.

Fig. 11 shows the collet enlarged in side elevation Fig. 9.

not wish to so limit my invention. I The housing is longitudinally split throughout, at least at the lower portion of its length, by

longitudinal vertical front slot 2, extending radially through the front of the housing .into the bore thereof whereby the-lower end of the housing constitutes a radially eXpansible and contractile split clamp,-forme d with forwardly extending parallel spaced front ears 8, transversely perforated, one of which is tapped, for the passage of horizontalfront rotary threaded clamping bolt 4, exteriorly accessible at one end at least, for manualrotat-ion to contract the lower end of the housing or to permitthe same to expand by reason of the natural resiliency-of the metal of the split ring. 7 v I V i' In the embodiment shown, the front ver-J tical radial slot 2, in the lower end' of the housing to render said lower end contractile, is extended vertically from said split clamp inthe form of vertical guideway 2a, having parallel longitudinal side walls, to accommodate a forwardly projectinglug 5, movable vertically in said slot andslidable along said parallel edge walls, to maintain a 'longitw from a diflerent angle than that. of n Fig. 12 shows the colletenlarged in outer is a detail horizontalsection on, the line 14-44:, Fig. 1.

dinally slidable non-rotary spindle barrel or sleeve 6, confined in the housing bore, against rotary or axial movement, and also forming an element of cutter depth stop means, hereinafter described.

However, in this embodiment, the vertical guide slot 2a, terminates short of the upper end portion of the housing which forms an unbroken circle surrounding the vertical bore.

The longitudinally-hollow non-rotary spindle barrel or sleeve 6, is arranged lon gitudinally of the housing bore and usually extends approximately throughout the bore length and depends from the lower end thereof, and carries the rotary cutter spindle 7, which is mounted to rotate therein and is carried thereby to and from the work. a

The lower end of spindle 7, depends from the lower end of the slide sleeve 6, and carries any suitable rotary cutter or other tool 8. The spindle 7, projects upwardly from the upper end of slide sleeve 6, in the example shown, and to an elevation above the cutter head housing, to receive the cutter spindle drive, as more fully explained hereinafter. The vertical bore of the cutter head housing is preferably cylindrical and of uniform diameter through out its length.

The spindle barrel 6, is also exteriorly cylindrical although its lower portion is of reducedd-iameter with respect to its upper portion, whereby the intermediate annular downwardly facing shoulder 6a, is formed. The large exterior diameter portion of the barrel or sleeve above the shoulder 6a,;snugly and slida-bly fits the cylindrical surface of the bore, -and at its rear longitudinal portion is provided with gear rack 61), preferably cut in the barrel, by which the barrel is raised and lowered to feed the cutter to and from the work. Thebarrel'is-thus raised and lowered by gear 8, meshing with said rack and fixed on =cross shaft 9, extending horizontally through and mounted in the cutter head, in rear of the barrel vided with'exterior handle 9a. 7

The lower'end of the barrel 6, extends *throug'h and slidably and snugly fits the cylindrical inner surface of a comparativelyshort cylindrical contractile meta-l bearing 6, and 'pro- 7 ring -or=bushing 10,-normally 'fixedlyclamped in the lower end of the housingbore, by the bushing con'tracting split ring clamp frmation thereof. This bushing 10, is forced upwardly into the housing bore through the lower-end thereof, and is heldrigidly-therein by tightening bolt 4 and thereafter, as re-- curring-barrel looseness develops from wear,

s'uch looseness can, in each progressive instance, be taken up, by TLTIt-l'lQI' PI'OgIQSSVGlY r'educing or=tightening the clamp from-time to time -to 'repeatedly further contractor re- '-d'uce=the bushing '10,-on and around the-barrel. The bushing is removable for replacement, when the split clamp is expanded by loosening the clamping bolt. The exterior cylindrical surface of the spindle barrel and the cylindrical surfaces of the removable guide ring 10, are accurately ground and relatively formed to maintain an accurate guidingfit between the lower end of the barrel and the interior of the ring to avoid lateral looseness of the barrel.

A coiled spring 12, is arranged exteriorly and longitudinally of the barrel and compressed between shoulder 6a and the top edge of ring 10, to approximately float or coun terb-alance the weight of the barrel and its load, in the operation of raising and lowering the same.

I The rotary cutter spindle 7, is provided at its projecting lowerend with means, hereinafter described, for rigldly holding the de pending axially alined cutter 8, and providing for removal and replacement of cutters. Therotary spindle 7, extends longitudinally through and is centrally arranged in its barrel, and is held'therein against objectionable relative longitudinal and radial movements by suitable end and radial thrust bearings.

For instance,l show the rotary cutter spindle 7, carried by its non-rotary barrel 6, through the medium of upper and lower sets of ball bearings 141, 15, clamped in place by nut 14a, on intermediate screw threaded por tion of spindle 7, and ring nut 15a, projecting down from and screwed up into the enlarged low-er end of the bore of barrel 7, and more or less snugly surrounding the enlarged cylindrical depending lower end of said spindle.

l/Vithout limitation as to the means employed .to secure the cutter 8, to and depending from the cutter spindle and without limitation as to the driving means employed to rotate the cutter spindle or how and where such driving means is applied to the cutter spindle, reciprocation of the cutter spindle barrel carries the cutter to and from the work and holds the cutter to operation in the work, and depth stop means cooperating with the barrel predetermines the working depth of the cutter in the work, and it is highly desirable that such depth stop be exceedingly accurate and capable of micrometer adjustment. In the example shown, the lug 5, constitutes an element of the'depth stop mechanism ormeans. This lug is of substantial rigid construction and dimensions and is rigidly fixed to the spindle barrel 6,and projects forwardly radially therefrom through and forwardly beyond the vertical guide slot 2a, and the flat bottom horizontal face ofsaid lug provides the abutmentstop face 5a, that overhangs the opposing flat top abutment stop face 17a, of a vertically adjustable stop :member 17, supported independentlyof lug cutting depth of cutter The 'sto member 17 is formed by an enlarged cylin rical nut, head or finger wheel the top surface of which provides the stop face 17a, in annular fiat horizontal form. The head 17, is integral or rigid 'with an elongated internally screw threaded sleeve 17?), upstanding from and axially alined with head 17. The rotary nut formed by preferably knurled finger head 17, and sleeve 17?), longitudinally receives and meshes with the longitudinal screw thread of vertical elongated fixed screw threaded shaft 18, carrying said nut which is vertically adjustable by rotation thereon.

The fixed shaft 18, carriedby a vertical bracket 19, fixed to the front of the cutter head housing to one side of the vertical plane of the guide slot 2a. This bracket has rigid upper and lower lateral arms 19a, receiving the ends of shaft 18, and in which said ends are normally fixed. The shaft 18, and consequently the nut 17, 17b, thereon, is spaced forwardly from and located directly in front of guide slot 211, with the sleeve 17b, of said nut in advance of lug 5, and with the rear portion of head 17, of the nut located under lug 5, to limit the downward movement thereof.

The cylindrical circumference of the head 17 is arranged close to the adjacent vertical edge of bracket 19, the front face of which is provided with a vertical scale s, and the head 17, is also provided with a circumferential scale 0. The scale 8, preferably reads down: wardly from zero and the graduations can be in inches, subdivided, say into quarters and twentieths, with one complete revolution of the nut equal to one twentieth of an inch vertical movement of the nutreading on scale s. The ra-durations of scale 0, can be in thousandths of an inch, whereby the cutting depth of the cutter 8, can be set within a thousandth of an inch.

To avoid danger of accidental movement of the stop nut 17 176, after being'set to the cutting depth desired, I provide a quickacting clamp to lock the nut against movement with respect to its shaft 18, and supporting bracket 19. In the particular embodiment shown, this clamp consists of a resilient metal split ring or band 20, normally loosely surrounding the cylindrical sleeve 17 b, of the nut and formed in one piece with a fiat laterally projecting shank 20a. extending transversely across the bracketv 19, and removably fitted in a transverse depressed socket or seat extending across the front of said bracket above the scale 8.

tion of its length with the slot at its inner end opening into the resilient contractile ring l recelves a clamping or ring contracting head- The shank 20a, is longitudinally slotted, at 20?), throughout a PCT".

ed screw21, which screws into a tappedhole in the floor of the shank receiving socket in bracket 19, to removably hold the shank to the bracket and to contract and permit ex pansion of the resilient band or ring clamp 20. .By tightening up the clamping screw 21, the clampQO, is contracted to tightly hold the nut 17, againstrotation. By loosening the screw 21, the resiliency of the metal Will cause expansion of ring 20, and release the nut for rotary adjustment.

,Merely as. an example ofan appropriate drive for the cutter spindle 7 I show a spindle drive pulley 23, on. the upwardly ex H tended end of the pulley, the spindle and 1 pulley being splined together so that the pulley is always operatively coupled tothe spindle to drive the same and the spindle is free to move vertically through the pulley.

The pulley is adapted to be rotated by any suitable belt or other driving transmission. The pulley is mounted on and carried by an upstanding sleeve 24, fixed in and extending down through .a hub 25, fixed in the upper end of the borethrough the cutter head housing. The rotary cutter spindle extends through and to a'point above the sleeve 24', and the drive. pulley. f The lower end head 7?) of the rotarycutter spindl'e'is' of enlarged diameter and exteriorly cylindrical where it depends through and fits and rotates in the ring nut 15a. The spindle is hollow throughout its length, and in head 7b,the spindle bore enlarges or flares to the end opening of the spindle so that the lower 1'. 1

end of the bore is inthe form of an upwardly contractlng cone, to receive and contract the longltudinally tapered cutter holding and gripping. collet 27, extending upwardly in and longitudinally of the spindle and having the internally longitudinally threaded shank 27 a, as usual, that receives and meshes with the longitudinally threaded lower end of the draw bar 28,-extending upwardly within the spindle and above the upper end thereof provided with handle 28a by which the draw bar can be rotated in the'spindle, when the spindle is held against rotation, to draw the collet upwardly tightly into the tapered bore to rigidly clamp the cutter to and in the spindle,'or-to rotate the draw bar in the opposite direction to permit the collet to move down and open to release and receive cutters.

The collet 27, is rendered expansible and contractile, in the example shown by three ,1 5,;

uniformly spaced longitudinal slots 2%, extending through its lower end upwardly part way the length of the collet.

The longitudinal shank portion of the col let is formed, in this example, with three longitudinal elongated uniformly spaced flats 270, to cooperate with three complementary inwardly-projecting radial similar pins 29,

respectively, carried by the rotary spindle, to prevent rotation of the collet relative to the spindle and to permit relative longitudinal movement of thecollet. These pins areconi posedof strong hard material and are headed at their outer ends and are slipped into countersunk radial uniformly spaced holes drilled in th mary'c aer spindle a reduced portion of the upper end of the bottom end "head of said spindle. The pins are of sufficient length to project into the bore of the spindle and engage shapes of the collet. These strong 'pins' are. locked against outward movementby exteripr ring 30, driven to permanent positoin on said reducedupper end of the spindle head exteriorly covering and backing the pin heads.

This arrangement permits the util aati on of strong hard pins and reduces p n breakage and dam'age to the minimum and by the employment of collet flats in comb nation w th the pin ends, it is an easy and quick opera tion to insert the, collet in and withdraw the same from the cutterspindlehead.

The flats. 270, are more or less loosely engaged by the. flats formed by the flat or squarely cut off inner ends of pins 29, as the inner. endsof the pins preferably barely clear the surfaces of flats 27.0, so that the collet is slightly free or loose yetis prevented by the pins from objectionable relative ax al movement in the spindle. In theepec fic embgd ment shown, three uniformly spaced plus 2%), are employed, yet I donot wish tothusln nt the broader phase of this feature of my Hi vention. Specifically considered, the cpl let is thus driven from several balanced points, namely; the flats and pin ends, and an exceedingly rugged durable, ClI'lYG. 18 provided w th possibility. of pinbreakage reduced to the minimum, and furthermore the collet can; be quickly and asily slipped to. operative pos tion in the spindle with not. more than. a possible third of a revolution to bring the flats and pin ends into registration This simple collet drive solves the heretofore serious problem of drive pin breakage and: drive, pm

displacement. v

I do not herein make claim to that feature of the disclosure hereof involving the contractile bushing 10, and a clamp or holder for progressively contracting the. bush ng around the barrel to take up recurring lateral 'looseness of the barrel developing from wear,

as I make claimbased on such feature in my application Serial No. 529 ,15"? filed April 10,1931, as acontinuation part offt heinstant case, I

It is evident that various changes, departures, additions, and modifications night be resortedto without, departing fromthe spirit and scope of my inventionsubstantially as defined by the following claims when construed in the light of the prior art to determine the scope to be accorded thereto, and hence the foregoing disclosure ispresented supporting housin as explanatory and not as limiting except vided with a portion of increased diameter forming an annular top stop abutment below and adapted, to abutthe bottom edge of said .lug to predetermine the cutting depth of the cutter carried by said spindle, a fixed longitudinal scale being provided along the path of'movement of said enlarged diameter portion, said enlarged portion having. a scale around the circumference thereof.

2. A cutter head assembly embodying a supporting housing having a longitudinal guide slot; a rotary cutter spindle barrel lon; gitudinally arranged and slidable in said housing and provided with a cutter depth stop member projectingoutwardly through said slot; a bracket normally fixedto the exterior of said. housing and provided withv a normally fixed screw threaded shaft parallel with and spaced outwardly from the path of movementof said slide stop member; a rotary nut meshing with the screw thread of and ad ustable vertically on said shaft and provld ing an annular stop face in the path of movement of said stop member to abut the same and predetermine the working depth of M the rotary spindle cutter, said nut having a visible scale around the circumference thereof, and said bracket providing a. longitudinal visible scale for reading in connection with said nut and the scale thereof; A

' 3. A cutter head assembly embodying a e g a rotary cutter spindle slide. longitudinally arranged and slidable in said housing and having a' cutter depth stop member movable longitudinally therewith;

a rotary longitudinally adjustable sleeve providing an abutting face in the path of movement of said stop memberlto constitute an opposing stop for predetermining the working depth of the cutter spindle; means including a normally stationaryscrew-threaded,portion supporting said sleeveat the exterior of the housing and rendering thesleeve longitudinally adjustable by rotation; and a.contractile"manually-operated clamp supported at the heusing exterior for. locking said sleeve agalnst accidental rotat on when set to the desired adj ustment.

4. A. cutter head assembly embodying a supporting housing; a rotary adjusting mem- 3' ber;and a contractile spring ring clamp embracing said member and provided with a lateral shank whereby the clamp is supported at the exterior of the-housing independently of the member, said clamp provided with a clamping screw for contracting the clamp to lock said member and for permitting the clamp to expand to release said member, said screw confining said shank to its support.

5. A cutter head assembly. embodying a supporting housing, a rotary cutter spindle carried thereby and extending longitudinally therethrough, said spindle havinga longitudinal bore at one end flared to provide a collet contracting taper; a tapered split expansible cutter clamping collet longitudinally movable in said. end of the spindle bore, a draw rod in said bore having screw threaded connection withsaid collet, said collet having an exterior fiat; a pin extending radially through the spindle and projecting into the bore thereof to engage said flat to prevent relative rotation of the collet and a station- 1 ary ring on the spindle and holding said pin against outward movement.

6. A cutter head assembly embodying a rotarycutter spindle having a bore with a flared tapered end and a series of spaced radial holes, headed pins in said holes and pro- 'ectin into the bore a rin surroundin the Y D 7 5 Ci spindle and holding the pins against cutward movement; and a cutter clamping ex- A, pansible collet and its controlling draw bar,

said collet exteriorly and longitudinally formed-to be engaged and held against relative rotation by said pins.

7. A cutter head assembly embodying a.

, rotary cutter head spindle having a longitudinal bore and a radial hole extending into said bore, a pin in said hole and at its inner .end projecting a limited distancemto sa1d bore, an exterior relatively fixed ring on said spindle andholding'said pin against outward movement, and a cutter holding collet removably held in said bore and having a'longitudinal exterior fiat for engagement by said pinto hold the collet to rotation with the spindle. I

. 8. In acutter tion; a rotary cutter spindle; a reciprocatory barrel carrying said spindle and by which said'spindle is moved to and from the work and held in working and withdrawn posi-. .tions; a support for and relatively stationary with respect to said barrel; and depth stop means for setting the limit of movement of saidbarrel toward the work. to determine the working depth or plane of the rotary cutter, said means including an elongated normally fixed scale carried. by and visible at the exterior of saidsupport and having its longitudinal axis parallel with the path of the reciprocation of said barrel, a bar- .rel depth, stop membermovable with said barrel; an annular longitudinally adjustable head assembly, in combinarotary complementary depth stop member constantly arranged in the path of movement of said barrel member toengage the rotary member having a visible scale around its periphery adjacent to and forreading in connection with said longitudinal scale.

9. In a cutter head assembly, inbombination; a housing; a rotary cutter spindle barrel slidable in said housing toward and from the work, and provided with the rotary cutter spindle; a visible elongated unit scale;

a rotary depth stop member arranged adjacentto said elongated scale and' adjustable and visible with said longitudinal, scale from the exteriorof the housing; supporting and adjusting'meanswhereby said rotary mem- -longitudinally thereof and'provided with an: frictional circular .scale around itsperiphery her is adjustable in either direction alongand longitudinally ofsaid longitudinal scale and is held in the relative position to which adjusted; and a-complementary depth stop memberto cooperate withsaid rotary member-in limiting the movement of the barrel toward the work. V

10. Ina cutter head assembly, in combination; ahousing having a longitudinalf'slot; abarrel slidable longitudinally of said housmg and having abarrel depth-stop lug mov able longitudinally. therewith and located in said slot and thereby holding the barrel against, rotary movement a complementary opposing depth stop member located in the longitudinal path of movement of said lug to limit the movement of the barrel toward the work; and supporting means for said member carried by the housing and whereby said member is manually adjustable longj-f-l:

tudinally of said path'of movement and :.1

held in the position to which adjusted.

'11.fIn combination; a support; a rotary cutter spindle; acarrier therefor movable longitudinally to carry determine the working depth of the cutter: and depth stop means :to predeterminesaid working'depth, including an elongated YlS- .ible scale parallel with said: path of move beside said scale and having a circumferential visible scale forreading in connecthe cutter of saidspindle toward and from. the work andto of said members being rotatable and located tion with said elongated scale; said rotatable memberbeing adjustable longitudinally with irespectto said elongated scale by rotation and providing aniannular stop surface opposing :sa1d member movable with the carrier.

'12. In combination ;'a-support; a carrier, a [IOtiLIJYCUttGI' spindle carried'there'bytoward and from the work with respect'to the sup- .port; a visible elongated unit scale arranged 'longitudinally'oi'the path of carrier move mentftoward and from the work; a rotary idepth stop memberifor cooperating with said vcarrier to predetermine the limit ofmovementrthereof towardthe work, and arranged besidesaid scale and adjustablelongitudinalilyfthereof by rotationiandprovided with an annular visible fractional scale "for reading with said unit scale; and a screw threaded supporting connection for said stop member whereby said member. isby rotation adjustaible longitudinally with respect {tosaid jpath of'movement and is held in I the position -to which-adjusted. r r ."13. 'Incombination; a support; airotary cutter spindle carrier movable with respect tosaid support toward and "fromthe work (and provided withthe rotary 'cuttertspindle a visibleie'longated unit scale;-a rotary'depth stop member arranged adjacentto said'longated scale and adjustable longitudinally with respect thereto and provided with a fractional circumferential scale visible beside for reading with 'saidlongitudinal scale said stop memberiprovidi'ngfan;annular stop surface; supporting and adjusting means whereby saidrotarymeniberis adjustable in either direction along; and longitudinally of said longitudinal scale "and is held inthe relative positionto'whi c'h adjusted; and'a complementary depth A stop member to "cooperate with the ianndlar surface of said Totary memberjin limiting the movement of said carrier toward thework 1'4. "In combination; a support; *a rotary cuttenspindlej a longitudinallyreciprocatory carrier for said spindle and b'y which said spindle is moved to andr'from "the work; and depth stop means .for setting the limit of movement'of'said carrier toward the workto pre determine theworkin g deptlrof the'r'otary 'cutter, includinga depth stop 'member mov- Iablewith said carrier, an annular longifinemberbyrrotati'on is adj usted longitudinal- *tudinally adjustable rotary complementary depth stop member having a single annular stop surface arranged in the'path 01'' movement of; said carrier member "to engage t-he "same I and limit "the movement of the 1 carrier 'tjo'ward'the work, and a screwthreaded sup- ;portingjconnection between-saidrotary member "and "said support whereby said rotary with respect to the [path of movement "of the carrier and is'held'inthe position'towhich adjusted.

I5. In combination; a rotary cutterspindle and its carrier; fme'ans forflongitudinally feedingthe same towardandfrom thework', a support :for said carrier; and: cutter depth stop "mechanism "embodying a carrier depth stop member movable toward and from the work with said carrier, and a normally sta- 'tional y complementary rotary depth stop member to cooperate withsaid first named memberin'limitin'g the carrier'niovementtoward thework screw threaded means; wherei by "said frota'ry "member is supported independently of said carrier and whereby said rotarylmember by rotation'is adjusted tovariou's -positions along the path "of'm'ovement of said 1carrier1nember,:said irotary 'member having 'aicir'cular visible scale; and visible -normally fixed scale for reading with said circular scale and elongated beside the 'path of adjusting movement of saidrotary 'member.

' 16. Inc0IIlbiI1tltiOI1;'a"rOtary cutter-spindle and its carrier; said carrier being-'Inovableto carry the "cutter of' said spindle *towardand 'fromthe"work-andtodeterminethe working depth ofsaid cutter; agg'uidin'g supportifor said carrier; and cutterdepthstopmechanism for predetermininglthe working "depth of said cutter,:embodying acarrierstop'niember moving therewith, anormally fixed bracket on said support,-'a.normallyzstationarystop 7 member in 'thejpath'ofzmovement of saidcarrier'member .to cooperate therewith in liniiting the spindle movement toward .the work, 'means supporting said normally stationary stop member from'saidfbra'cket'and wherebyMOO said lasbmentioned 'membercanhe adjusted -and;held at variouspositions along said'path of movement, an elongated scale besidesaid normally stationar-yzmeniber:and'carried by said "bracket for guidance in 'adjustingsaid last mentionedmeniber, "and meansior tempofrarily locking said normally. stationary i-meni'ber' in itsfadjusted positions.

I7. A cutter head "assembly "embodying a rotary cutter: spindle 'ihaving a ilonjgitudinal' b'ore providing a :collet contracting portion,

said spindle havingara dialhole opening into said bore, a ,pin pro3ect1ng from 'said hole into sa d "bore 'EIII'GXlSGIlOI rlng holdingsald pin against outwardmovement insaid'ho'l'e;

and a removable tapered contractile cutter holding collet longitudinally arrangedin said b'ore,isaid"collet havinga shank provided-with a "longitudinal depression extending to the inner "end thereof to cooperate with the in ner "end "of said pin to drive the collet :with the spindle and to permit longitudinal *removaliand insertion of the collet.

'18, A cutterhead'assemblyincludingjarotary cutter spindle having a longitudinal bore providing a co-llt contracting portion and a longitudinally movable tapered contractile cutter holding 'ccillet longitudinally arranged and m'ovable in saidbore, and pro vided withnieans for moving the same longitudinally in said bore to contract and permit 7 expansion of said collet, said collet having a shank formed with wide exterior longitudinal flats extending to the shank end, said spindle having means extending into said bore to cooperate with said flats in driving the collet and in permitting longitudinal movement of the collet in the spindle and removal and insertion thereof.

10 19. In combination; a support; a carrier provided with a rotary cutter spindle, said carrier being movable with respect to said support to carry the cutter toward and from the work, said carrier having an exterior projecting depth stop movable therewith toward and from the work to limit the working depth of said cutter; a rotary sleeve having an annular stop abutment located below said depth stop to abut the same and determine said outter working depth; and a normally-fixed elongated threaded shaft arranged longitudinally beside the path of movement of said 7 depth stop and supported exteriorly and independently of said carrier, said sleeve being threaded on said shaft and adjustable ap proximately throughout the length thereof by rotation with said annular stop abutment intersecting the path of movement of said depth stop throughout the longitudinal adjustments of said sleeve by rotation on said shaft.

Signed at Racine, county of Racine, Wisconsin, this 11th day of July, 1929.

GEORGE GORTON. 

